Japanese Patent Laid-Open Publication No.10-504397 discloses a conventional analyzer that uses an optical disc, such as a compact disc to record audio or video data thereon, and an optical disc drive for reproducing the data to analyze a specific component of a test sample by tracing tracks on the optical disc with the test sample arranged thereon.
FIG. 8 is a top view of analyzing disk 1100 used for a conventional analyzer. Disk 1100 is formed according to the standard of a conventional optical disc for recording audio or video data thereon and is provided with track 1101 which has address data and is formed with pits and grooves.
Analyzing disk 1100 includes centrifuge chamber 1102, measuring chamber 1103, overflow chamber 1105, and analysis chamber 1104 which are provided thereon. Centrifuge chamber 1102 has inlet 1108 through which a test sample, such as blood, is input, and the input test sample is centrifuged in the chamber. Measuring chamber 1103 collects a predetermined amount of the centrifuged test sample. Overflow chamber 1105 stores the rest of the test sample other than the sample collected in measuring chamber 1103. Analysis chamber 1104 analyzes the test sample supplied from measuring chamber 1103. These chambers are connected with each other with capillary tube 1109, a minute duct. Analysis chamber 1104 can store a reagent, for example, for examining a color reaction with the test sample.
Japanese Patent Laid-Open Publication No.2003-270128 discloses that the position of each chamber can be specified by the analyzer based on the positional relationship of each chamber with trigger patterns 1106 and 1107. Trigger patterns 1106 and 1107 are provided on an outer circumferential edge of analyzing disk 1100 by printing or the like. Trigger pattern 1106 is used to specify the position of centrifuge chamber 1102, and trigger pattern 1107 is used to specify the positions of measuring chamber 1103 and analysis chamber 1104.
Analyzing disk 1100 includes four sets each having the chambers and the trigger patterns arranged on the circumference separated from each other. Analyzing disk 1100 is produced by bonding a substrate with the chambers thereon onto a disk having the track with the address data recorded thereon.
FIG. 9 is a block diagram of a conventional analyzer using analyzing disk 1100. The analyzer has a structure of a conventional optical disc drive. More specifically, the apparatus includes optical pickup 1020 for illuminating disk 1100 with laser, traverse motor 1021 for moving optical pickup 1020, spindle motor 1022 for rotating disk 1100, servocontrol circuit 1024 for controlling these components, signal processing circuit 1025 for converting a signal from optical pickup 1020 into data, and controller 1023 for controlling these circuits. Photodetector 1011 detects laser emitted from optical pickup 1020 and transmitted through disk 1100. A signal corresponding to the detected laser is converted into digital data by analog/digital (A/D) converter 1013. The digital data is processed by signal processing circuit 1014 and is stored in RAM 1016. Controller 1015 controls signal processing circuit 1014 and RAM 1016. Photosensor 1017 detects trigger patterns 1106 and 1107 provided on disk 1100.
An operation of analyzing disk 1100 and the analyzer treating blood as the test sample. The blood, the test sample is input through inlet 1108 of analyzing disk 1100. Analyzing disk 1100 is into the analyzer. The analyzer executes spin-up processes including disk discrimination, focus adjustment, and tracking adjustment, to prepare for tracing track 1101 provided on analyzing disk 1100.
First, centrifugation is executed to separate a target component from the others in the test sample. The blood, the test sample, exists in centrifuge chamber 1102 of analyzing disk 1100 and is centrifuged into a blood cell component and a plasma component while analyzing disk 1100 rotates at a predetermined rotation speed for a predetermined time. The plasma component is used to monitor the level of cholesterol and glucose.
After the centrifugation completes, analyzing disk 1100 stops its rotation. When analyzing disk 1100 stops, the blood plasma to be tested which is separated in centrifuge chamber 1102 at the inner circumference side of the disk is transferred and collected into measuring chamber 1103 through capillary tube 1109 due to capillarity. Analyzing disk 1100 rotates again at a predetermined rotation speed for a predetermined time in order to measure the collected blood plasma component, and then, the rotation of analyzing disk 1100 is stopped. When the rotation is stopped, the blood plasma component to be tested starts to be transferred from measuring chamber 1103 to analysis chamber 1104. Then, disk 1103 starts rotating again, and the entire target blood plasma component reacts with a reagent input in analysis chamber 1104.
After these processes complete, optical pickup 1020 moves to the radial position of analysis chamber 1104, and starts tracing track 1101 of analyzing disk 1100 at the position. Then, trigger pattern 1107 provided on analyzing disk 1100 is detected by photosensor 1017. Light transmitting from optical pickup 1020 through analysis chamber 1104 is detected by photodetector 1011 for a predetermined time after trigger pattern 1107 is detected by photosensor 1017. A signal corresponding to the detected light is converted to digital data by A/D converter 1013, and the data is stored in RAM 1016. The level of cholesterol, glucose, and the like in the blood plasma component to be tested is monitored bade on the stored data, and an analysis result is provided.
In the conventional analyzer, it is not confirmed, during or after the centrifugation, whether a target component and the other component, i.e., the blood plasma component and a cell component, are separated from each other in centrifuge chamber 1102. If they are not separated appropriately, a component interfering with analysis which is to be separated ordinarily flows into measuring chamber 1103 and analysis chamber 1104. If the plasma component and the cell component of blood is not centrifuged completely, capillary tube 1109 connecting centrifuge chamber 1102 with measuring chamber 1103 may be clogged with the cell component. In this case, the predetermined amount of the plasma component is not collected in measuring chamber 1103, accordingly preventing the plasma component from being analyzed accurately.